Changeset - b10adac1ab7c
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Mads Kiilerich (mads) - 6 years ago 2020-03-06 16:58:47
mads@kiilerich.com
auth: make it explicit that _check_permission only use the less strict pull checking for actual pull actions
1 file changed with 6 insertions and 6 deletions:
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kallithea/lib/base.py
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@@ -89,405 +89,405 @@ def _get_ip_addr(environ):
 
        return _filter_proxy(ip)
 

	
 
    ip = environ.get(proxy_key2)
 
    if ip:
 
        return _filter_proxy(ip)
 

	
 
    ip = environ.get(def_key, '0.0.0.0')
 
    return _filter_proxy(ip)
 

	
 

	
 
def get_path_info(environ):
 
    """Return PATH_INFO from environ ... using tg.original_request if available.
 

	
 
    In Python 3 WSGI, PATH_INFO is a unicode str, but kind of contains encoded
 
    bytes. The code points are guaranteed to only use the lower 8 bit bits, and
 
    encoding the string with the 1:1 encoding latin1 will give the
 
    corresponding byte string ... which then can be decoded to proper unicode.
 
    """
 
    org_req = environ.get('tg.original_request')
 
    if org_req is not None:
 
        environ = org_req.environ
 
    return safe_str(environ['PATH_INFO'].encode('latin1'))
 

	
 

	
 
def log_in_user(user, remember, is_external_auth, ip_addr):
 
    """
 
    Log a `User` in and update session and cookies. If `remember` is True,
 
    the session cookie is set to expire in a year; otherwise, it expires at
 
    the end of the browser session.
 

	
 
    Returns populated `AuthUser` object.
 
    """
 
    # It should not be possible to explicitly log in as the default user.
 
    assert not user.is_default_user, user
 

	
 
    auth_user = AuthUser.make(dbuser=user, is_external_auth=is_external_auth, ip_addr=ip_addr)
 
    if auth_user is None:
 
        return None
 

	
 
    user.update_lastlogin()
 
    meta.Session().commit()
 

	
 
    # Start new session to prevent session fixation attacks.
 
    session.invalidate()
 
    session['authuser'] = cookie = auth_user.to_cookie()
 

	
 
    # If they want to be remembered, update the cookie.
 
    # NOTE: Assumes that beaker defaults to browser session cookie.
 
    if remember:
 
        t = datetime.datetime.now() + datetime.timedelta(days=365)
 
        session._set_cookie_expires(t)
 

	
 
    session.save()
 

	
 
    log.info('user %s is now authenticated and stored in '
 
             'session, session attrs %s', user.username, cookie)
 

	
 
    # dumps session attrs back to cookie
 
    session._update_cookie_out()
 

	
 
    return auth_user
 

	
 

	
 
class BasicAuth(paste.auth.basic.AuthBasicAuthenticator):
 

	
 
    def __init__(self, realm, authfunc, auth_http_code=None):
 
        self.realm = realm
 
        self.authfunc = authfunc
 
        self._rc_auth_http_code = auth_http_code
 

	
 
    def build_authentication(self, environ):
 
        head = paste.httpheaders.WWW_AUTHENTICATE.tuples('Basic realm="%s"' % self.realm)
 
        # Consume the whole body before sending a response
 
        try:
 
            request_body_size = int(environ.get('CONTENT_LENGTH', 0))
 
        except (ValueError):
 
            request_body_size = 0
 
        environ['wsgi.input'].read(request_body_size)
 
        if self._rc_auth_http_code and self._rc_auth_http_code == '403':
 
            # return 403 if alternative http return code is specified in
 
            # Kallithea config
 
            return paste.httpexceptions.HTTPForbidden(headers=head)
 
        return paste.httpexceptions.HTTPUnauthorized(headers=head)
 

	
 
    def authenticate(self, environ):
 
        authorization = paste.httpheaders.AUTHORIZATION(environ)
 
        if not authorization:
 
            return self.build_authentication(environ)
 
        (authmeth, auth) = authorization.split(' ', 1)
 
        if 'basic' != authmeth.lower():
 
            return self.build_authentication(environ)
 
        auth = safe_str(base64.b64decode(auth.strip()))
 
        _parts = auth.split(':', 1)
 
        if len(_parts) == 2:
 
            username, password = _parts
 
            if self.authfunc(username, password, environ) is not None:
 
                return username
 
        return self.build_authentication(environ)
 

	
 
    __call__ = authenticate
 

	
 

	
 
class BaseVCSController(object):
 
    """Base controller for handling Mercurial/Git protocol requests
 
    (coming from a VCS client, and not a browser).
 
    """
 

	
 
    scm_alias = None # 'hg' / 'git'
 

	
 
    def __init__(self, application, config):
 
        self.application = application
 
        self.config = config
 
        # base path of repo locations
 
        self.basepath = self.config['base_path']
 
        # authenticate this VCS request using the authentication modules
 
        self.authenticate = BasicAuth('', auth_modules.authenticate,
 
                                      config.get('auth_ret_code'))
 

	
 
    @classmethod
 
    def parse_request(cls, environ):
 
        """If request is parsed as a request for this VCS, return a namespace with the parsed request.
 
        If the request is unknown, return None.
 
        """
 
        raise NotImplementedError()
 

	
 
    def _authorize(self, environ, action, repo_name, ip_addr):
 
        """Authenticate and authorize user.
 

	
 
        Since we're dealing with a VCS client and not a browser, we only
 
        support HTTP basic authentication, either directly via raw header
 
        inspection, or by using container authentication to delegate the
 
        authentication to the web server.
 

	
 
        Returns (user, None) on successful authentication and authorization.
 
        Returns (None, wsgi_app) to send the wsgi_app response to the client.
 
        """
 
        # Use anonymous access if allowed for action on repo.
 
        default_user = User.get_default_user(cache=True)
 
        default_authuser = AuthUser.make(dbuser=default_user, ip_addr=ip_addr)
 
        if default_authuser is None:
 
            log.debug('No anonymous access at all') # move on to proper user auth
 
        else:
 
            if self._check_permission(action, default_authuser, repo_name):
 
                return default_authuser, None
 
            log.debug('Not authorized to access this repository as anonymous user')
 

	
 
        username = None
 
        #==============================================================
 
        # DEFAULT PERM FAILED OR ANONYMOUS ACCESS IS DISABLED SO WE
 
        # NEED TO AUTHENTICATE AND ASK FOR AUTH USER PERMISSIONS
 
        #==============================================================
 

	
 
        # try to auth based on environ, container auth methods
 
        log.debug('Running PRE-AUTH for container based authentication')
 
        pre_auth = auth_modules.authenticate('', '', environ)
 
        if pre_auth is not None and pre_auth.get('username'):
 
            username = pre_auth['username']
 
        log.debug('PRE-AUTH got %s as username', username)
 

	
 
        # If not authenticated by the container, running basic auth
 
        if not username:
 
            self.authenticate.realm = self.config['realm']
 
            result = self.authenticate(environ)
 
            if isinstance(result, str):
 
                paste.httpheaders.AUTH_TYPE.update(environ, 'basic')
 
                paste.httpheaders.REMOTE_USER.update(environ, result)
 
                username = result
 
            else:
 
                return None, result.wsgi_application
 

	
 
        #==============================================================
 
        # CHECK PERMISSIONS FOR THIS REQUEST USING GIVEN USERNAME
 
        #==============================================================
 
        try:
 
            user = User.get_by_username_or_email(username)
 
        except Exception:
 
            log.error(traceback.format_exc())
 
            return None, webob.exc.HTTPInternalServerError()
 

	
 
        authuser = AuthUser.make(dbuser=user, ip_addr=ip_addr)
 
        if authuser is None:
 
            return None, webob.exc.HTTPForbidden()
 
        if not self._check_permission(action, authuser, repo_name):
 
            return None, webob.exc.HTTPForbidden()
 

	
 
        return user, None
 

	
 
    def _handle_request(self, environ, start_response):
 
        raise NotImplementedError()
 

	
 
    def _check_permission(self, action, authuser, repo_name):
 
        """
 
        Checks permissions using action (push/pull) user and repository
 
        name
 

	
 
        :param action: 'push' or 'pull' action
 
        :param user: `User` instance
 
        :param action: 'push' or 'pull'
 
        :param user: `AuthUser` instance
 
        :param repo_name: repository name
 
        """
 
        if action == 'push':
 
            if not HasPermissionAnyMiddleware('repository.write',
 
                                              'repository.admin')(authuser,
 
                                                                  repo_name):
 
                return False
 

	
 
        else:
 
        elif action == 'pull':
 
            #any other action need at least read permission
 
            if not HasPermissionAnyMiddleware('repository.read',
 
                                              'repository.write',
 
                                              'repository.admin')(authuser,
 
                                                                  repo_name):
 
                return False
 

	
 
        else:
 
            assert False, action
 

	
 
        return True
 

	
 
    def _get_ip_addr(self, environ):
 
        return _get_ip_addr(environ)
 

	
 
    def __call__(self, environ, start_response):
 
        try:
 
            # try parsing a request for this VCS - if it fails, call the wrapped app
 
            parsed_request = self.parse_request(environ)
 
            if parsed_request is None:
 
                return self.application(environ, start_response)
 

	
 
            # skip passing error to error controller
 
            environ['pylons.status_code_redirect'] = True
 

	
 
            # quick check if repo exists...
 
            if not is_valid_repo(parsed_request.repo_name, self.basepath, self.scm_alias):
 
                raise webob.exc.HTTPNotFound()
 

	
 
            if parsed_request.action is None:
 
                # Note: the client doesn't get the helpful error message
 
                raise webob.exc.HTTPBadRequest('Unable to detect pull/push action for %r! Are you using a nonstandard command or client?' % parsed_request.repo_name)
 

	
 
            #======================================================================
 
            # CHECK PERMISSIONS
 
            #======================================================================
 
            ip_addr = self._get_ip_addr(environ)
 
            user, response_app = self._authorize(environ, parsed_request.action, parsed_request.repo_name, ip_addr)
 
            if response_app is not None:
 
                return response_app(environ, start_response)
 

	
 
            #======================================================================
 
            # REQUEST HANDLING
 
            #======================================================================
 
            set_hook_environment(user.username, ip_addr,
 
                parsed_request.repo_name, self.scm_alias, parsed_request.action)
 

	
 
            try:
 
                log.info('%s action on %s repo "%s" by "%s" from %s',
 
                         parsed_request.action, self.scm_alias, parsed_request.repo_name, user.username, ip_addr)
 
                app = self._make_app(parsed_request)
 
                return app(environ, start_response)
 
            except Exception:
 
                log.error(traceback.format_exc())
 
                raise webob.exc.HTTPInternalServerError()
 

	
 
        except webob.exc.HTTPException as e:
 
            return e(environ, start_response)
 

	
 

	
 
class BaseController(TGController):
 

	
 
    def _before(self, *args, **kwargs):
 
        """
 
        _before is called before controller methods and after __call__
 
        """
 
        if request.needs_csrf_check:
 
            # CSRF protection: Whenever a request has ambient authority (whether
 
            # through a session cookie or its origin IP address), it must include
 
            # the correct token, unless the HTTP method is GET or HEAD (and thus
 
            # guaranteed to be side effect free. In practice, the only situation
 
            # where we allow side effects without ambient authority is when the
 
            # authority comes from an API key; and that is handled above.
 
            from kallithea.lib import helpers as h
 
            token = request.POST.get(h.session_csrf_secret_name)
 
            if not token or token != h.session_csrf_secret_token():
 
                log.error('CSRF check failed')
 
                raise webob.exc.HTTPForbidden()
 

	
 
        c.kallithea_version = __version__
 
        rc_config = Setting.get_app_settings()
 

	
 
        # Visual options
 
        c.visual = AttributeDict({})
 

	
 
        ## DB stored
 
        c.visual.show_public_icon = str2bool(rc_config.get('show_public_icon'))
 
        c.visual.show_private_icon = str2bool(rc_config.get('show_private_icon'))
 
        c.visual.stylify_metalabels = str2bool(rc_config.get('stylify_metalabels'))
 
        c.visual.page_size = safe_int(rc_config.get('dashboard_items', 100))
 
        c.visual.admin_grid_items = safe_int(rc_config.get('admin_grid_items', 100))
 
        c.visual.repository_fields = str2bool(rc_config.get('repository_fields'))
 
        c.visual.show_version = str2bool(rc_config.get('show_version'))
 
        c.visual.use_gravatar = str2bool(rc_config.get('use_gravatar'))
 
        c.visual.gravatar_url = rc_config.get('gravatar_url')
 

	
 
        c.ga_code = rc_config.get('ga_code')
 
        # TODO: replace undocumented backwards compatibility hack with db upgrade and rename ga_code
 
        if c.ga_code and '<' not in c.ga_code:
 
            c.ga_code = '''<script type="text/javascript">
 
                var _gaq = _gaq || [];
 
                _gaq.push(['_setAccount', '%s']);
 
                _gaq.push(['_trackPageview']);
 

	
 
                (function() {
 
                    var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
 
                    ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
 
                    var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
 
                    })();
 
            </script>''' % c.ga_code
 
        c.site_name = rc_config.get('title')
 
        c.clone_uri_tmpl = rc_config.get('clone_uri_tmpl') or Repository.DEFAULT_CLONE_URI
 
        c.clone_ssh_tmpl = rc_config.get('clone_ssh_tmpl') or Repository.DEFAULT_CLONE_SSH
 

	
 
        ## INI stored
 
        c.visual.allow_repo_location_change = str2bool(config.get('allow_repo_location_change', True))
 
        c.visual.allow_custom_hooks_settings = str2bool(config.get('allow_custom_hooks_settings', True))
 
        c.ssh_enabled = str2bool(config.get('ssh_enabled', False))
 

	
 
        c.instance_id = config.get('instance_id')
 
        c.issues_url = config.get('bugtracker', url('issues_url'))
 
        # END CONFIG VARS
 

	
 
        c.repo_name = get_repo_slug(request)  # can be empty
 
        c.backends = list(BACKENDS)
 

	
 
        self.cut_off_limit = safe_int(config.get('cut_off_limit'))
 

	
 
        c.my_pr_count = PullRequest.query(reviewer_id=request.authuser.user_id, include_closed=False).count()
 

	
 
        self.scm_model = ScmModel()
 

	
 
    @staticmethod
 
    def _determine_auth_user(session_authuser, ip_addr):
 
        """
 
        Create an `AuthUser` object given the API key/bearer token
 
        (if any) and the value of the authuser session cookie.
 
        Returns None if no valid user is found (like not active or no access for IP).
 
        """
 

	
 
        # Authenticate by session cookie
 
        # In ancient login sessions, 'authuser' may not be a dict.
 
        # In that case, the user will have to log in again.
 
        # v0.3 and earlier included an 'is_authenticated' key; if present,
 
        # this must be True.
 
        if isinstance(session_authuser, dict) and session_authuser.get('is_authenticated', True):
 
            return AuthUser.from_cookie(session_authuser, ip_addr=ip_addr)
 

	
 
        # Authenticate by auth_container plugin (if enabled)
 
        if any(
 
            plugin.is_container_auth
 
            for plugin in auth_modules.get_auth_plugins()
 
        ):
 
            try:
 
                user_info = auth_modules.authenticate('', '', request.environ)
 
            except UserCreationError as e:
 
                from kallithea.lib import helpers as h
 
                h.flash(e, 'error', logf=log.error)
 
            else:
 
                if user_info is not None:
 
                    username = user_info['username']
 
                    user = User.get_by_username(username, case_insensitive=True)
 
                    return log_in_user(user, remember=False, is_external_auth=True, ip_addr=ip_addr)
 

	
 
        # User is default user (if active) or anonymous
 
        default_user = User.get_default_user(cache=True)
 
        authuser = AuthUser.make(dbuser=default_user, ip_addr=ip_addr)
 
        if authuser is None: # fall back to anonymous
 
            authuser = AuthUser(dbuser=default_user) # TODO: somehow use .make?
 
        return authuser
 

	
 
    @staticmethod
 
    def _basic_security_checks():
 
        """Perform basic security/sanity checks before processing the request."""
 

	
 
        # Only allow the following HTTP request methods.
 
        if request.method not in ['GET', 'HEAD', 'POST']:
 
            raise webob.exc.HTTPMethodNotAllowed()
 

	
 
        # Also verify the _method override - no longer allowed.
 
        if request.params.get('_method') is None:
 
            pass # no override, no problem
 
        else:
 
            raise webob.exc.HTTPMethodNotAllowed()
 

	
 
        # Make sure CSRF token never appears in the URL. If so, invalidate it.
 
        from kallithea.lib import helpers as h
 
        if h.session_csrf_secret_name in request.GET:
 
            log.error('CSRF key leak detected')
 
            session.pop(h.session_csrf_secret_name, None)
 
            session.save()
 
            h.flash(_('CSRF token leak has been detected - all form tokens have been expired'),
 
                    category='error')
 

	
 
        # WebOb already ignores request payload parameters for anything other
 
        # than POST/PUT, but double-check since other Kallithea code relies on
 
        # this assumption.
 
        if request.method not in ['POST', 'PUT'] and request.POST:
 
            log.error('%r request with payload parameters; WebOb should have stopped this', request.method)
 
            raise webob.exc.HTTPBadRequest()
 

	
 
    def __call__(self, environ, context):
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